Abradant supplying device



Jun'e.l5, 1937. K. c. BURROUGHS 2,083,773

' ABRADANT SUPPLYING DEVICE Filed Feb. 28, 1955 as so a2 26 I8 l2 W I w 1 4" FIG UT V 111/ IO M KENNE TH C. BURROUGHS INVENTOR ATTORNEY Patented June 15, 1937 UNITED STATES PATENT OFFICE to Bausch.& Lomb ptical Company, Rochester, N. Y., a corporation of New York Application February 28 1935, Serial No. 8,673

7 Claims. 01. 51-263) The present invention relates to apparatus for supplying abradants and more particularly to apparatus for supplying abradants suspended in a fluid.

When abradants such as emery or rouge are used in grinding or polishing operations, they are usually suspended in a fluid such as water or oil. The abradant tends to settle out of the water and when it settles forms hard and dense 0 sediment. One of the major difficulties in the handling of such abradants is to prevent such settling with its attendant fouling of pipes and containers. Once this sediment forms in a pipe it is very diflicult to remove. At the present time this settling is prevented by keeping the abradant mixture always moving and by flushing the entire abradant supply system with clear water when the grinding or polishing operation is completed. 1 One of the objects of the present invention is to provide a new and improved apparatus for supplying abradants. Another object is to providea new and improved apparatus for supplying abradants in which the abradant is prevented frornsettlingin the supply pipe. A further ob- -j6013 is to provide a new and improved abradant supply device operated by compressed air. A further-object is to provide a new and improved apparatus for supplying abradants in which the abradant mixture need not be removed when the 3 apparatus is stopped. A further object is to provide a new and improved abradant supply device in which the stirring rod can be removed from the abradant when the device is stopped.

These and other objects and advantages reside in certain novel features of construction, ar.- rangement and combination of parts as will hereinafter be more fully set forth and pointed out in the appended claims.

Referring to the drawing:

Fig. 1 is a vertical sectional view of an apparatus embodying this invention showing parts in elevation.

Fig. 2 is a top plan view of the operating pulley showing the actuating cam.

In certain grinding or polishing operations, such as for example the grinding or polishing of lenses or mirrors, the lens 10 is placed on a support II, the tool [2 is driven across the face of the lens and a suitable abrading or polishing 5O agent such as emery or rouge is periodically introduced between the lens l0 and tool l2. In order to prevent the generation of excessive heat during the grinding or polishing the emery or rouge 5 is suspended in a suitable lubricating agent such as water and the mixture is periodically applied between the lens l0 and tool i2.

A preferred form of abradant supplying mechanism embodying this invention is illustrated in the drawing wherein i3 indicates a. supply tank for containing the emery or rouge suspended in water. A supply tube' it extends into' the tank l3 and terminates near the bottom of the tank while the other end of the tube M is directed toward the lens It. The tube it is so formed that the abradant and water mixture cannot remain still within it since, unless the mixture being forced through the tube, it will be siphoned back into the tank I3. There is no part of the tube M where the abradant could settle to form a hard mass and thus foul the tube.

A conduit l5 extends from a source of compressed air, not shown, into the tank l3 and is under the control of anadjustable valve l6 and a cut-off valve H. The cut-off valve I! has a knob or head I8 which is urged outwardly by a spring 19 to close the valve 11 in the conduit l5. When the knob I8 is pressed inwardly opening the valve ll, the pressure in the tank 13 is increased. and the abradant mixture is forced through the tube l4 between the tool l2 and lens I0. A small opening 20 is provided in the tank l3 fora purpose to be hereinafter described.

A bearing 21 is formed on the top wall of the tank l3 and a bracket 22 mounted on the top Wall of. the tank carries a second bearing 23 in alignment with the bearing 2|. A stirring rod 24 carrying a paddle 25 is rotatably and slidably mounted in the bearings 2|. and 23. Between the two bearings 2| .and 23 is a pulley 26 adapted to be driven by a belt 21 fromta source of power, not shown. The pulley 26 is provided with an inwardly extending key 28 which engages the longitudinal slot 29 in the stirring rod 24. A cam 30 is fixed to the pulley 26 for periodically striking the knob l8 and actuating the valve I1 to supply abradant to the work.

The apparatus is driven by the belt 21 which drives the pulley 26. The stirring rod 24 is slidably keyed'to the pulley 26 so that the abradant and fluid will be agitated during the whole time that the apparatus is running. As the pulley 26 is rotating at substantially constant speed, the cam 3|] will open the valve H for fixed periods of time. The amount of abradant supplied during these periods can be controlled by the valve I6. Due to the extreme elasticity of air, if the tank 13 were entirely closed, a continuous pressure would be built up in the tank, even though the air were supplied intermittently through the conduit l5. This is prevented by the opening which opens into the atmosphere. The opening 20 is so small however that it does not prevent the building up of pressure while the valve I1 is open.

When the apparatus is stopped the stirring rod 24 and paddle 25 are raised so that the abradant will not settle around the paddle and so make it diflicult to start the apparatus. The long keyway 29 engaging the key 28 makes it possible to drive the stirring rod 24 while it is being lowered when the apparatus is to be restarted. In this way the paddle digs into the solid cake of abradant which has settled to the bottom of the tank and decreases the time for getting the abradant in suspension.

From the foregoing it is apparent that I am able to attain the objects of my invention and provide a new and improved apparatus for supplying abradants in which it is not necessary to flush the entire system after each run, since the abradant cannot settle in the tubes. Various modifications can, of course, be made without departing from the spirit of my invention or the scope of the appended claims.

I claim:

1. An abradant supplying device comprising a substantially closed tank adapted to hold an abradant suspended in a fluid, an abradant carrying tube, one end of said tube extending into said tank and terminating near the bottom thereof, the other end of said tube being outside of said tank and being so formed that no abradant can settle therein and means for selectively introducing compressed air into said tank to increase the pressure therein.

2. An abradant supplying device comprising a substantially closed tank adapted to hold an abradant suspended in a. fluid, an abradant supply tube so formed'that no abradant can settle therein having one end extending into said tank and terminating near the bottom thereof, means for selectively introducing compressed air into said tank to increase the pressure therein and means for preventing the maintainance of a pressure within the tank after the compressed air is cut oil.

3. An abradant supplying device comprising a substantially closed tank adapted to hold an abradant suspended in a fluid, an abradant supply tube so formed that no abradant can settle therein having one end extending into said tank and terminating near the bottom thereof, means for selectively introducing compressed air into said tank to increase the pressure therein and means for preventing the maintainance of a pressure within the tank after the compressed air is cut off, said last-named means comprising an air vent in the tank.

4. An apparatus of the class described comprising a substantially closed tank adapted to contain an abradant suspended in a fluid, an abradant supply tube leading from said tank, a conduit for supplying compressed air to said tank, a valve for controlling said conduit, a stirring rod rotata'bly carried by said tank extending into said tank for agitating the abradant, drive means for actuating said stirring rod and cam means actuated by said drive means for controlling said valve.

5. An abradant supplying device comprising a substantially closed tank, a tube extending into said tank and terminating near the bottom, thereof, the other end of said tube being outside of said tank, said tube being so formed that no abradant can settle therein, a pulley rotatably mounted on top of said tank, a stirring rod slidably keyed in said pulley and extending into said tank, a compressed air conduit extending into said tank, a spring valve for controlling said compressed air, a cam on said pulley for controlling said air and an air vent in said tank adjacent the top thereof, said air vent being so formed and proportioned that the air pressure in said tank will be maintained only while said valve is open.

6. An apparatus of the class described comprising a substantially closed tank, a tube having one end directed toward a grinding tool and the other end extending downwardly into said tank and terminating near the bottom thereof, said tube being so formed that no abradant can settle therein, a source of compressed air, a conduit leading from said source to said tank to increase the pressure in said tank, a valve in the conduit for controlling the air pressure at the outlet end and means in said conduit for opening or closing said conduit completely.

7. An apparatus of the class described comprising a substantially closed tank, a tube having one end directed toward a grinding tool and the other end extending downwardly into said tank and terminating near the bottom thereof, said tube being so formed that no abradant can settle therein, a source of compressed air, a conduit leading from said source to said tank to increase the pressure in said tank, a valve in the conduit for controlling the air pressure at the outlet end and means in said conduit for opening or closing said conduit completely, said means comprising a valve normally closing said conduit and means for selectively actuating said valve.

KENNETH C. BURROUGHS. 

